Archive for category science
Exercise reduces fatigue — a counter-intuitive effect
My RSS feed from the Curious Cat Science and Engineering Blog alerted me to news from ScienceDaily about overwhelming evidence that regular exercise increases energy levels. Professor Patrick O’Connor, co-director of the University of Georgia laboratory that analyzed 70 randomized trials on 6,807 subjects, said:
When people are fatigued the last thing they want to do is exercise.
However, the positive effect of exercise on energy was very consistent — seen in over 90 percent of the trials studied by the UGA researchers.
I feel sure this is true to some extent. I certainly feel charged up after doing a half-hour cardio-workout on my Endurance E4 elliptical. This machine features nothing very fancy for display. It only provides exercise — pure and simple at low impact.
For less anecdotal support for the hypothesis that exercise reduces fatigue, see this report from the University of Oslo. If you feel otherwise — drained by exercise, consider stocking up on a supply of jelly beans. Possibly these ‘sports beans’ ward off fatigue. I advise some skepticism if the findings prove positive, because according to ScienceDaily the study is funded in part by The Jelly Belly Candy Company. See their tasty-looking product at ZombieRunner.
Mercury — a transitory mote in the eye of the sun
On Wednesday residents of my hemisphere saw (?) the planet Mercury transit the sun. This happens only about every decade. One really couldn’t see Mercury because it is so small relative to the sun, which burns far too brightly for the naked eye to withstand. I watched the transit live from an astronomer’s view (Kitt Peak, Arizona*) via the webcast by San Francisco’s Exploratorium. The funny thing is that a speck in their Meade 16 inch reflector’s optics showed up more prominently than Mercury itself. For a perspective on how small this planet appears from earth (only 1/200th the diameter of the sun) see this photograph from VisualUniverse.org. Nevertheless, when Mercury first hit the edge of the sun, the astronomer directing the webcast said the he and his colleague were doing a little “happy dance”! 🙂 By virtue of owning an 8-inch Meade reflector, I am a very amateurish astronomer myself. Seeing Mercury was a rare treat worth savoring. Here’s something really rare that’s reported at Wikipedia: On July 5, 6757 residents in Eastern Siberia can watch the simultaneous occurrence of a solar eclipse and a transit of Mercury. If you want to see this, I advise you go there now, drink a barrel of vodka, set your atomic-powered alarm clock 4751 years ahead and, finally, bury yourself in the snow. Good luck and mind the mastodons!
*Located by red star on map showing zones of visibility. For great views of the telescopes, background narration and the transit itself, click the RealVideo link to the saved webcast.
Drinking twice as much reduces heart attack by factor of three?
After suffering a mild heart attack (an oxymoron!) a few years ago, I asked the cardiologist if it’s true that a glass of red wine a day keeps the myocardial infarctions away. He said “yes.” What about white, I wondered. “That works too,” said he. Encouraged by this, I wondered if beer might work too. The answer was affirmative. Next I questioned whether two drinks might be even better. After that got endorsed by the cardiologist, I quit while I was ahead. I’ve enjoyed one glass of beer or wine, and occasionally a second helping, every day since. Life is good!
Today I was heartened to see in the HeartCenterOnline Newsletter that a study by Beth Israel Deaconess Medical Center in Boston indicates that two drinks daily help men avoid heart attack. At first glance at the following detail I thought I ought to have more than two drinks:
“There were 9 heart attacks in a group of 714 men who drank more than two drinks daily, and 34 in a group of 2,252 who drank less than two a day.” Unfortunately, if you do the math and calculate the percents by comparison, this statistic becomes a lot less compelling for those who like their liquor. I am holding the line at one drink every day for sure and two at the most, but only when I want to really live it up.
Sound from Sand: Rock Music?
At a vastly smaller scale than Stonehenge, stones ground by natural forces to a well-rounded and relatively regular shape can make very distinctive sounds, which you can hear at song of the Atacama Desert dunes in Chile. According to physicist Stephane Doudy of the Centre de la recherche scientifique in Paris, the volume of sand slides can reach a nearly unbearable 110 decibels — on par with a jet engine. For the complete story of how “self-synchronized avalanches turn piles of sand into musical instruments,” check out Dulcet Dunes by Fenella Saunders of American Scientist magazine. What I find fascinating is that it evidently takes a veneer of salt to make sand sing, so if you really want to hear a tune from a dune, head for a desert that spills into the sea.
Longer-term perspective on global warming (and other catastrophes)
On March 16th I blogged about the sharp upturn in global temperatures that some liken to the blade of a hockey stick. The blog provides a link to a graph reproduced by the BBC which goes back 1000 years. Aside from questions about how data are fitted, simple changes to scales and other attributes of the graphs themselves can paint very different perspectives on seemingly straightforward scientific questions such as whether we ought to be worried about global warming. Andy Sleeper shows this in part 7 of his white paper titled HOW TO LIE WITH STATISTICAL GRAPHICS. The color-coded graph generated by the U.S. National Oceanographic and Atmospheric Administration is very alarming. However, it only provides 122 years of history and the y-axis scale is restricted to about 2 degrees C. A few figures later in Sleeper’s paper one sees another graph based on 400,000 years of temperatures estimated from core samples of Antarctic ice. It reveals cyclic temperature swings of 12 degrees C! In this context, should a less than 1 degree increase in global temperature be considered abnormal, that is, due to a special cause such as man-made carbon dioxide?
PS. Here’s something to really worry about. The November issue of Sky and Telescope features a heads-up on “The Most Dangerous Asteroid Ever Found” — a 1000-foot pile of rock called Apophis. It will just miss the Earth on April 13, 2029. If Apophis hits a narrow zone — called the keyhole, it will be dragged enough by our gravity to put it on a course that collides with Earth seven years later. One can only hope that NASA’s proposed gravity tractor will pull the asteroid off target and save the planet.